A5062207652- Turtle Biology and Conservation
- Animal Behavior and Reproduction
- Amphibian and Reptile Biology
- Genetic and Clinical Aspects of Sex Determination and Chromosomal Abnormalities
- Reproductive biology and impacts on aquatic species
- Aquaculture disease management and microbiota
- Animal Nutrition and Physiology
- Wildlife Ecology and Conservation
- Avian ecology and behavior
- Physiological and biochemical adaptations
- Animal Genetics and Reproduction
- Bird parasitology and diseases
- Sperm and Testicular Function
- T-cell and B-cell Immunology
- Insect and Pesticide Research
- Invertebrate Immune Response Mechanisms
- Reproductive Physiology in Livestock
- Birth, Development, and Health
- Plant and animal studies
- Estrogen and related hormone effects
- Effects and risks of endocrine disrupting chemicals
- Insect and Arachnid Ecology and Behavior
- Antimicrobial Peptides and Activities
- Hormonal and reproductive studies
- Immune Response and Inflammation
Illinois State University
2016-2025
Wake Forest University
2024
Google (United States)
2010-2022
University of Illinois Urbana-Champaign
2014
Urbana University
2014
Iowa State University
2004-2011
Indiana University Bloomington
2000-2006
Agricultural Research Service
1998
University of Colorado Boulder
1996-1998
Early embryonic exposure to maternal glucocorticoids can broadly impact physiology and behaviour across phylogenetically diverse taxa. The transfer of offspring may be an inevitable cost associated with poor environmental conditions, or serve as a effect that alters phenotype in preparation for stressful environment. Regardless, are likely have both costs benefits paid collected over different developmental time periods. We manipulated yolk corticosterone (cort) domestic chickens ( Gallus...
We describe the genome of western painted turtle, Chrysemys picta bellii, one most widespread, abundant, and well-studied turtles. place into a comparative evolutionary context, focus on genomic features associated with tooth loss, immune function, longevity, sex differentiation determination, species' physiological capacities to withstand extreme anoxia tissue freezing.Our phylogenetic analyses confirm that turtles are sister group living archosaurs, demonstrate an extraordinarily slow rate...
Most hypotheses that have been put forward in order to explain the persistence of environmental sex determination (ESD) reptiles assume a relatively fixed association with temperature-induced phenotype and no maternal influence on offspring sex. Here we demonstrate maternally derived yolk hormone levels ratio describe two new aspects temperature-dependent (TSD), i.e. seasonal variation both thermal response steroid levels. Eggs from painted turtles (Chrysemys picta) were incubated at 28...
Conditions experienced early in life can influence phenotypes ecologically important ways, as exemplified by organisms with environmental sex determination. For temperature‐dependent determination (TSD), variation nest temperatures induces phenotypic that could impact population growth rates. In environments vary over space and time, how does this key demographic parameters (cohort ratio hatchling recruitment) stages of populations exhibiting TSD? We leverage a 17‐year data set on painted...
Patterns of temperature fluctuations in nature affect numerous biological processes, yet, empirical studies often utilize constant treatments. This can limit our understanding how thermally sensitive species respond to ecologically relevant temperatures. Research on turtles with temperature-dependent sex determination (TSD) provides good examples this, since nest temperatures from many populations rarely exceed those necessary produce females under laboratory conditions. We hypothesized that...
Evidence for a developmental relationship between B cells and macrophages has led to the hypothesis that evolved from phagocytic predecessor. The recent identification of IgM+ in fishes amphibians supports this hypothesis, but raises question when, evolutionarily, was capacity lost cells? To address this, leucocytes were isolated red-eared sliders, Trachemys scripta , incubated with fluorescent beads analysed using flow cytometry confocal microscopy. Results indicate slider are able ingest...
The primary function of the immune system is to protect organism from invading pathogens. In vertebrates, this has resulted in a multifaceted comprised both innate and adaptive components. all jawed vertebrates complex, but unlike endothermic relatively little known about functioning ectothermic vertebrate system, especially reptilian system. Because turtles are long-lived ectotherms, factors such as temperature age may affect their response, comprehensive studies lacking. We investigated...
Summary Optimal egg size theory predicts that females should produce propagules of a and number maximize maternal fitness. However, studies the allocation resources to eggs have rarely provided evidence such optimization. This is presumably because constraints limit reproductive allocation. One example pelvic aperture morphology constraining in turtles. Growing suggests even this classic incomplete. Hormones regulate both cycle vitellogenic activity turtles may provide novel physiological...
Abstract In the painted turtle ( Chrysemys picta) and red‐eared slider Trachemys scripta) , temperature that eggs are exposed to during incubation determines sex of developing embryo. Constant experiments have shown for each these species there is a pivotal produces 1:1 ratio; higher temperatures bias ratios toward females, lower males. Few studies examined how fluctuating temperatures, as would be experienced in natural nests, affect hatchling phenotype. Models predict under determination...
In birds, maternally derived yolk steroids are a proposed mechanism by which females can adjust individual offspring phenotype to prevailing conditions. However, when interests of mother and differ, parent–offspring conflict will arise embryonic interests, not those the mother, should drive response maternal in eggs. Because this potential conflict, we investigated ability developing bird embryos process steroids. We examined how progesterone, testosterone oestradiol levels changed both...
All vertebrate embryos develop in the presence of maternally derived steroids, and maternal steroids have been hypothesized to link phenotype offspring physiology. In placental vertebrates, it is known that are metabolized during development via sulfonation pathway. We used eggs from red-eared slider turtle (Trachemys scripta) determine whether same metabolic pathway metabolize an oviparous vertebrate. To examine relationship between estradiol estrogen sulfates development, levels were...
Variable environmental conditions can alter the phenotype of offspring, particularly in ectothermic species such as reptiles. Despite this, majority studies on development reptiles have been carried out under constant laboratory, raising question just how applicable those investigations are to natural conditions? Here, we first review what learned from these constant-temperature studies. Second, examine importance temperature fluctuations for and highlight outcomes conducted fluctuating...
Summary The field of eco‐immunology seeks to address the causes and consequences natural variation in immune responses. Recently, development more immunological resources for nonmodel systems along with growing availability genomic data has made it feasible explore complex differences systems. Cytokines are small molecular weight proteins that major signalling molecules system. Studies mice humans have demonstrated importance tightly regulated cytokine signalling, thus, cytokines may play a...
Despite classical expectations of a trade-off between immune activity and reproduction, an emergent view suggests that individuals experiencing activation their system actually increase reproductive effort allocation to offspring as form terminal investment in response reduced survival probability. However, the components mechanisms increased parental following immunostimulation are currently unknown. We hypothesize glucocorticoid production modulates constitutes investment. activated...
In the painted turtle (Chrysemys picta) and red‐eared slider (Trachemys scripta), temperature that eggs are exposed to during incubation influences many traits of developing embryo. We tested effect fluctuating‐ versus constant‐temperature regimes at high low ends viable developmental range assess environment on offspring development. Eggs were incubated in four treatments: 23°C constant, 23° ± 3°C, 31°C 31° 3°C. assessed duration, hatchling survival, growth, immune function via a...
Nesting behaviour is critical for reproductive success in oviparous organisms with no parental care. In where sex determined by incubation temperature, nesting may be a prime target of selection response to unbalanced ratios. To produce an evolutionary change sex-ratio selection, components must heritable. We estimated the field heritability two key population painted turtles (Chrysemys picta) temperature-dependent determination applying 'animal model' pedigree reconstructed from genotype...
Steroid hormones have long been studied by behavioral ecologists as a nongenetic means whereby females can influence the development of their offspring. In oviparous vertebrates, steroids are present in yolk at time oviposition and shown to affect numerous traits To date, most studies focused on functional relationship between offspring development. this article we used mechanistic approach investigate effects an attempt decipher how lipophilic may make it from lipid-rich developing embryo....
Aging is typically associated with a decrease in immune function. However, aging does not affect each branch of the system equally. Because these varying effects age on responses, could taxa differently based how particular taxon employs its resources towards different components defense. An example this found humoral system. Specific responses tend to while non-specific, natural antibody increase age. Compared mammals, reptiles all ages have slower and less robust Therefore, they may invest...
Characterizing how organisms respond to transient temperatures may further our understanding of their susceptibility climate change. Past studies in the freshwater turtle, Trachemys scripta , have demonstrated that timing and duration heat waves can major implications for response genes involved gonadal development production female hatchlings. Yet, no study has considered these cold snap exposure affect males. We investigated affects gene expression T. embryos an early influences resulting...
Abstract Inducible defence strategies evolve in response to temporally and spatially variable predation risk. Selection should favor the expression of these when risk crosses a threshold, but may also depend on how effective strategy is across contexts. For neotropical harvestmen, aggregation behavior group-level can be supplemented by additional enhance antipredator defence. A secondary behavioral termed “bobbing,” which individuals rapidly move their bodies up down, has been proposed...
Identifying sex of hatchling turtles is difficult because juveniles are not obviously externally dimorphic, and current techniques to identify often logistically unfeasible for field studies. We demonstrate a widely applicable inexpensive alternative detect subtle but significant sexual dimorphism in hatchlings, using landmark-based geometric morphometric methods. With this approach, carapace landmarks were digitized from photographs each hatchling, shape variables generated after variation...
Life-history theory predicts that, in long-lived organisms, effort towards reproduction will increase with age, and research from oviparous vertebrates largely supports this prediction. In reptiles, where parental care occurs primarily via provisioning of the egg, older females tend to produce larger eggs, which turn hatchlings that have increased survival. We conducted an experimental release study report maternal age positively influences offspring survivorship painted turtle ( Chrysemys...